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Cosmetic Chemists Meet in Barcelona

More than 1000 cosmetic chemists attended the 25th Congress of the IFSCC. Technical sessions were devoted to active ingredient research, efficacy assessment and trends in formulations.

Tom Branna
Editorial Director

More than 1000 cosmetic chemists from around the world converged on Barcelona last month for the 25th Congress of the International Federa-tion of Societies of Cosmetic Chemists (IFSCC). Attendees said that they were impressed with the level of presentations. At the same time, the Spanish Society put on a social program with considerable flair. Technical sessions were devoted to a wide range of topics, including research in active ingredients, assessment of cosmetic efficacy and formulation trends. In addition, the Congress featured more than 300 poster presentations, while the technical exhibition featured products and services from more than 60 industry suppliers.

The Congress opened with a keynote presentation by Antonio Ferrer-Monteil of Miguel Hernández University. Dr. Ferrer-Monteil described the relationship between neurogenic inflammation and sensitive skin. He explained that when the neuroimmune system is damaged, it causes neurogenic inflammation via afferent and efferent fibers, which in turn, trip a family of sensory receptors including TRPV1. The speaker detailed how TRPV1 antagonists may have applications as cosmetic ingredients since they act as inflammatory agents.

Daniel Maes of Estée Lauder

Daniel Maes, Estée Lauder, provided details on the Maturation Index, a new marker of the differentiation process that reflects the condition of the epidermal barrier function as it relates to the structure of highly cross-linked rigid corneocytes.

His team found that the proper development of the skin barrier can only be reached if the rate of cellular proliferation and differentiation is controlled in such a way to allow for full maturation of the corneocytes.

Shiseido’s Yoshimasa Miura followed with a presentation on a novel in vitro SPF algorithm which offers simultaneous compensation for UV filter photostability. The method employed a new system consisting of a light source, liquid light guide, integrating sphere, optical fiber, double-monochromator and UV photomultiplier tube. According to Dr. Miura, this in vitro method is capable of accurately estimating even high SPF sunscreens under solar simulated light, at a dose as high as 2.00 mg/cm2—identical to conditions that are employed for in vivo measurements. Dr. Miura and his team are in the process of establishing a global inter-laboratory validation of the method.

Novel Materials

During a session devoted to actives, Tomo Osawa of Shiseido detailed the development and benefits of a water-resistant/detergent-washable powder coated with a stimuli-responsive polymer. The material, a copolymer of 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS) and 11-methacrylamidoundecanoic acid (MAU), was obtained by radical polymerization and treated with titanium dioxide. The researchers developed a water-in-oil sun care product based on this AMPS/MAU-treated titanium dioxide, and it exhibited both water-resistance and detergent-washability.

Hiroto Tanamachi of Kao explained how his team used atomic force microscopy to study the effects of 18-MEA on hair. According to Kao’s study, the decrease in 18-MEA on the cuticle surface affects the hydrophobic-hydrophilic property in a wet environment more so than in a dry environment. Furthermore, 18-MEA allows hair fibers to lay flat and parallel to each other in wet environments by providing relatively high receding contact angles and low surface friction. Finally, hair alignment in the dry environment is directly affected by the hair alignment in the wet environment, particularly in the case of damaged hair, according to the presenter.

Isabelle Renimel of LVMH reviewed the effectiveness of a novel retinoid, (E)- 3,5,4’ trimetoxystilbene, on different markers of aged human skin. Her team observed an increase in different collagen expressions that was greater than a retinol cream (a positive control). The LVMH researchers demonstrated that (E)- 3,5,4’ trimetoxystilbene, a natural derivative of resveratrol, has applications in cosmetic formulations.

Michel Salmon of StatiCell explained how pro-vitamin D sterols (7-dehydrocholesterol and ergosterol) protect skin fibroblasts from becoming prematurely senescent after repeated UVB irradiation. He theorized that the protection is due to p53 translocation and subsequent activation in the nucleus that, in turn, induces natural repair of the damages induced by oxidative stresses. One hypothesis to explain this finding is that these molecules are agonist ligands of the alternative ligand binding domain of the vitamin D receptor, and are thus able to induce non-genotropic rapid effects in skin cells, according to Mr. Salmon.

Measurements

Greg Hillebrand, Procter & Gamble, detailed the advantages of using an image-based method to simulate facial aging. The technique has the ability to predict and visualize an individual’s unique future skin wrinkling and hyperpigmentation.

“People age uniquely, so it is difficult to predict what they’ll look like 5, 10 or 20 years from now,” he explained.

According to Mr. Hillebrand, by recognizing what the future may hold, doctors, their patients and consumers can better design a customized program aimed at slowing or even reversing the skin aging process. The process utilizes a Visia Complexion Analysis System from Canfield Scientific combined with wrinkle and pigmentation analyses on regions of interest, and spatial computer mapping. Mr. Hillebrand warned, however, that the technique is only able to simulate wrinkling 15-20 years in the future.

IFSCC Conference Set for Oct. 7-9 in Melbourne

The 25th Congress of the International Federation Societies of Cosmetic Chemists (IFSCC) just concluded in Barcelona, but plans are already well underway for the next IFSCC Conference, which will be held in Melbourne, Oct. 7-9 at the Melbourne Convention Exhibition Centre.

The theme of the conference is "A Corroboree of Science & Beauty." Deadline for abstract submission is Dec. 31, 2008. Deadline for notification of abstract acceptance is Jan. 31, 2009. Deadline for scientific manuscript submission is May 31, 2009.

For those looking even further ahead, the 26th IFSCC Congress is scheduled for Sept. 20-23, 2010 in Buenos Aires, Argentina. The theme of the event is: "Innovation & Responsibility: Cosmetics Forever."

Marianne Brandt of ProDerm explained how skin profilometry, ultrasound assessment of dermal intrusions of fat and skin temperature profiling are all useful quantitative parameters for the assessment of cellulite severity in clinical studies. She demonstrated how these techniques are adding robust and objective measurement data to complete subjective visual methods.

Anthony Rawlings, Procter & Gamble, explained how confocal raman spectroscopy (CRS) was utilized to compare the use of one commercially-available moisturizer with two others that were known to only alleviate dry skin. The total stratum corneum (SC) water content values obtained by CRS were compared with values obtained via capacitance measurement (corneometer). To facilitate the method, the P&G team had to validate the use of CRS to measure SC thickness by direct comparison with optical coherence tomography (OCT) at a variety of body sites. According to the speaker, CRS offers significant advantages over electrical measures, allowing more sensitive measurements and a step-change in information about stratum corneum water content.

Animal Testing Alternatives

Day 2 of the Congress opened with a keynote lecture by José Vincente Castell of the University of Valencia, Spain, who reported on the latest advances in test methods. While he acknowledged that at the moment there are no approved replacements for the Draize eye irritation test, he urged the audience to resort to Draize only when absolutely necessary. Alternatively, researchers should use cow eyes from slaughterhouses to conduct hazard assessments or Hen’s Egg Test Chorioallantoic Membrane (HET-CAM) tests. Other test methods detailed by Dr. Castell included the Local Lymph Node Assay, which he called a reduction and refinement in animal testing, the Buehler Test and the Magnusson and Kligman Guinea Pig Maximization Test to measure skin sensitization. Despite many advances made in animal testing alternatives, Dr. Castell noted that there is still no validated test method for inhalation and oral routes.

Of course, animals and their by-products are widely used in cosmetic formulation. Luigi Rigano, L. Rigano R&D Laboratories, explained how he obtained novel retinol-like actives from parrot feathers. His team isolated and extracted a mixture of polyenals, called psittacofulvins, and found that they have antioxidant properties and can influence cell proliferation. Using crotonic aldehyde as a starting material, his team synthesized congeners called parrodienes, before focusing its study on the 8 C atoms member of the family that the group termed “Parrotine.” In an anti-wrinkle study carried out on 12 volunteers over four weeks, a formula containing 0.28% Parrotine resulted in a visible decrease in wrinkle depth, while bioengineering characteristics were improved.

Skin Differences/Novel Materials

Stéphane Diridollou of L’Oréal discovered that micro relief, sebum excretion and skin dryness, as well as some skin structures are different based on ethnicity. In a study of nearly 400 women, L’Oréal researchers discovered that micro relief, sebum excretion and skin dryness, as well as some skin structures, vary by ethnic group. In addition, age effects are influenced by ethnicity, suggesting anatomical or physiological property differences in skin of people of different origins. More specifically, Chinese were found to produce less sebum, while African-Americans had drier skin as they aged. In addition, winter had a more pronounced effect on skin dryness among Caucasian women, than for other three groups tested (African Americans, Chinese and Mexican).

Regardless of skin color, all of today’s consumers want effective products. To help formulators create them, raw material suppliers have developed a wide range of novel ingredients. Delphine Rival of BASF explained how a Hibiscus abelmoschus seed extract acts as a protective active ingredient of FGF-2, a growth factor that ensures dermal fibroblast proliferation and enables them to synthesize matrix molecules that are essential to skin integrity. BASF researchers discovered that the extract protected FGF-2 via its intrinsic heparan sulphate-like effect and via a stimulation of sulphated glycosaminoglycan synthesis, which is a natural, protective molecule for FGF-2. A clinical study confirmed that the extract-based product significantly reduced wrinkles, while skin density and texture were improved, especially in older subjects.

Another natural active, Platycarya strobilacea extract (PSE), has applications as a anti-wrinkle cosmetic, according to Young Heui Kim of Bioland. In vitro tests demonstrated that the material had free radical scavenging activity, elastase inhibitory activity, expressed MMP-1 and synthesized type I collagen in normal human fibroblast cells. In clinical tests, the material showed good anti-wrinkle effects as measured by the visual evaluation of dermatologists, photometric evaluation, manufacture of skin replicas and image analysis using the Skin-Visiometer SV 600.

“In clinical trials of PSE, it was proven that the material is an active and safe anti-wrinkle ingredient for cosmeceuticals,” concluded Dr. Kim.

Masato Iino of Shiseido

Masato Iino, Shiseido, provided evidence of how adenosine can promote hair growth. He explained that adenosine receptors are located on the surface of dermal papilla cells (DPCs) in human hair follicles, and reminded the audience that adenosine is an important endogenous biomolecule involved in processes of human hair growth and loss. Adenosine activates FGF-7 production through its receptors in DPCs, and released FGF-7 contributes to the prolongation of the anagen (growth) phase by stimulating follicular epithelial cell proliferation. He concluded that application of exogenous adenosine as a topical hair lotion is effective in preventing androgenetic alopecia in men and female pattern hair loss in women.

Low molecular weight scleroglucan protects skin cells from dehydration by creating an extra-cellular matrix capsule. Its water-binding capacity and its numerous biological actives make it a candidate as an active ingredient in cosmeceuticals, according to Mike Farwick of Evonik. His team assessed the material using state-of-the-art analysis of gene expression, protein production and lipid formation. Using the genomics approach, LMW scleroglucan was proven to trigger keratinocyte differentiation as indicated by expression of one of its most potent promoters, PI3K/Akt, which also acts as protector from premature cell death. LMW scleroglucan was also found to stimulate barrier lipid formation by increasing cholesterol and ceramide levels in living skin equivalents. In vivo analysis revealed that depolymerized scleroglucan leads to improved moisturizing properties and improved skin feeling.

Andrew James of Unilever presented a paper devoted to histological investigations on the neurobiology of axillary skin. As a result of research conducted by Jennifer E. Pople, Unilever found that the increased amount of fillagrin that was found in axillary samples may be due to or in response to regular shaving. He concluded, however, that the results of the study suggest that axillary skin does show some differences in expression of neurogenic markers compared to an adjacent site, but whether this is an inherent feature or the result of physical challenges remains unknown.

Thursday, Oct. 9, marked the final day of the Congress. The session opened with a presentation by Dr. Maria Blasco of the Spanish National Cancer Research Center. Dr. Blasco reviewed some of the novel ways that researchers are combatting cancer.

During the general session, Cristina Carreno of DiverDrugs detailed a recent study of novel peptides for the stimulation of natural defensin production in the skin. Her team screened a combinatorial library of 32,768 synthetic tripeptides to identify potential hBD-2 boosters. Several candidates were active, and among them Peptide #8 (proposed INCI name: Tripeptide-40) proved to be able to induce both hBD-2 and hBD-3 endogenous synthesis, thus becoming an enhancer of the natural defense mechanisms. It is the first time that synthetic peptides have been found to boost natural defensin production, according to the speaker.

This peptide could be useful in the cosmetic industry to enhance the protective effect of the skin against the daily exposure to pathogens, and in the dermopharmaceutical industry to treat skin conditions that suffer from microorganism invasion and proliferation.

Lieve A.G. Declercq of Estee Lauder provided an indepth look at solar lentigines (age spots), via in vivo reflectance confocal microscopy, which is said to provide a new and revealing view of aged skin. According to the speaker, analysis by RCM provided in-depth information on the morphological changes in the structure of solar lentigines. The images revealed profound changes in the density of hyperrefractive dermal papillae in lesional skin compared to peri-lesional areas. Along with an increase in the number of dermal papillae there was a striking loss of circularity of the alignment pattern of hyperrefractive basal cells.

Confocal microscopy also offers a valuable tool to evaluate the efficacy of topical treatments in a non-invasive way. A four months treatment with ingredients that were selected for their ability to reduce the size of melanin clusters and quiet down inflammation successfully reduced the visual contrast and significantly improved the inner structure of solar lentigines.

Using Confocal Raman Spectroscopy, a team at CE.R.I.E.S. was able to assess the amino acid concentration of stratum corneum, explained Sophie Gardinier. Raman measurements were performed using the model 3510 Skin Composition Analyzer (River Diagnostics BV, Rotterdam, The Netherlands). This instrument is optimized for an in-vivo and non-invasive analysis of the skin molecular composition. It comprises a dispersive spectrometer with two laser excitations: 671 nm for optimized measurements in the 2500-4000 cm-1 region and 785 nm for the 400-2200 cm-1 region. Depth profiles of Raman spectra were measured from the skin surface to the viable epidermis (40 μm) in 2 μm depth increments in high wavenumber region (2500-4000 cm-1) to obtain the water concentration. Raman spectra were also recorded in the fingerprint region (400-2200 cm-1) in 4 μm depth increments to determine the concentration of lipids and NMF components. For each spectral region, a set of five spectra were acquired.

Twenty seven Caucasian women with healthy apparent skin were included in this study. They were aged from 35 to 45 and had skin phototype I – IIIa, no history or ongoing skin disease, no systemic or local treatment having a known effect on the skin, not sunbathed the month prior to the beginning of the study. Women were grouped according to the severity of the skin dryness on their forearm. Two groups were constituted as followed: group A constituted of 10 women with capacitance value <30 a.u. corresponding to individuals with “very dry skin” and group B constituted of 17 women with a capacitance value ≥30 a.u. corresponding to women with “dry to normal skin”. For more accuracy, clinical assessment of skin dryness was also performed by a trained dermatologist (0 = not dry, 1 = dry, 2 = very dry).

At baseline, free amino acids histidine and proline were found in higher concentrations in women from group A, as compared to individuals from group B. No significant difference was found between the two groups for the other measured components.

According to Dr. Gardinier, this study demonstrated the usefulness of in vivo confocal Raman spectroscopy to characterize epidermal changes associated with skin dryness. The high concentrations of histidine and proline in the group with the lower basal hydration level (group A) may indicate a disturbance of these amino acids metabolism during epidermal keratinization. The decrease of histidine and proline in response to twice daily application of a moisturizer might therefore be associated with a regulation of metabolic pathways within the SC, resulting in or contributing to the increase of SC hydration observed.

Frank Pflucker of Merck explained the benefits of a UV-photostable system in microcapsules with high UVA/B ratio. Thanks to microencapsulatopm. lipophilic butyl methoxydibenzolymethane (BMDBM) and octocrylene (OCR) can now be added to the hydrophilic water phase or to the final o/w emulsions to boost protect and create safe and efficient modern formulations.

In combination with other non-penetrating UV-filters such as titanium dioxide, zinc oxide, methylene bis-benzotriazolyl tetramethylbutylphenol, the microcapsules are a very beneficial raw material for day care, sun care, and baby care formulations. Microcapsulation improves UVA/B ratio performance data. Furthermore, existing oil-in-water formulations may be easily improved with respect to the UVA/B
ratio by adding the microcapsules to the outer phase where synergistic effects may also occur, according to Mr. Pflucker.

The results showed two different types of bicontinuous microstructures, cylindrical and lamella-like structures. Both bicontinuous microemulsion structures exhibited good cleansing ability, and the cleansing speed was rather faster for the cylindrical bicontinuous microemulsion. This relationship between the microstructures and cleansing ability encouraged Kao researchers to develop new makeup removers.

A lotion containing 1% Ceramide 2 acts as an effective skin barrier formula, according to Hidetaka Akatsuka of Pola. In his study, the author found that when mixing ceramide 2 and phytostrol S (PS) in a weight ratio of 1:1, lamellar structure with strong intermolecular force was formed. Furthermore, when incorporating sodium dilauramidoglutamide lysine, lamellar structures were swollen only in the hydrophilic groups while maintaining intermolecular force within the bilayers. The dispersion had a large tube structure. Furthermore, when it was dispersed in water using a high-pressure emulsification apparatus; Micro fluidizer, ultrafine (40nm) and flat vesicles and membranes could be prepared.
The author concluded that the ultrafine (40nm) and flat vesicles and membranes showed not only high barrier recovery index but also high permeability on both an in vitro and an in vivo test.

Robert Y. Lochhead of the University of Southern Mississippi, explained how high throughput screening methods can greatly enhance the study of surfactants, as well as the evaluation of polyelectrolyte thickeners. He provided details on how the order of addition of salt on conditioning shampoo pre-formulations affects a formula.

Dr. Lochhead noted that the correct rheologies and film formation capabilities are extremely important in gaining consumer acceptance and selection of the right thickeners is imperative. With this in mind, his team employs rapid evaluation methods for viscosity/rheology measurements that provide insight
into the structure and properties of polyelectrolyte-type thickeners. According to Dr. Lochhead, there are large differences in the intrinsic viscosities that measure the hydrodynamic volume of unit mass of the polymer in solution.

In his research, Dr. Lochhead found that the that the hydrophobic cross-links of the original polymer network were disrupted by surfactant adsorption, but re-established by polymer-micelle interaction at the onset of surfactant micelle formation. The onset of viscosity loss and thickening is strongly affected by the presence of salts and also by temperature. This provides guidance to formulators who wish to avoid unexpected changes in viscosities and also to those who wish to employ stimuli-responsiveness to their formulations.

Lars Ole Haustedt of AnalytiCon Discovery, explained how potential TRPV1 antagonists can be used treatments for sensitive skin. He noted that the TRPV1 receptor is a key player in inflammatory pain acting as a molecular integrator of noxious stimuli including thermal nociception and inflammatory hyperalgesia. He went on to detail how his company devised a system to reduce the complexity, improve the ease of synthesis and dramatically reduce the costs of starting materials.

Keiko Takada of Shiseido provided details on how winged bean extract can be used as an anti-aging treatment by targeting at Fibulin-5. Utlizing novel SEM techniques, Dr. Takada succeeded in visualizing the natural structure of elastic fiber along with collagen fiber and observed age-related ultrastructural alteration of elastic fiber which is presumed to trigger the reduction of skin resilience, resulting in sagging and wrinkle formation.

It was also found that fibulin-5 is a key substance for generating and maintaining elastic fibers in the dermis, and increasing fibulin-5 was effective for elastic fiber regeneration. By using a new screening system, more than 600 substances were tested for effects on elastic fibers, and it was determined that winged bean seed extract increased fibulin-5 synthesis and promoted elastic fiber regeneration. A test emulsion containing winged bean seed extract was also observed to improve skin wrinkles and increase stratum corneum moisture content in human skin. He concluded that the extract is expected to improve age-related reduction of skin resilience and is considered a promising anti-aging cosmetic ingredient.

Finally, Mitsuo Nakama of Nippon Menard explained how macrophage migration inhibitory factor (MIF) is a novel target to control the melanin content of human skin. MIF upregulated the protein level of tyrosinase in human melanocytes by preventing its degradation, not by accelerating its synthesis. In addition, MIF prevented the ubiquitination and proteasomal degradation of tyrosinase protein. On the other hand, Shirakami yeast extract restored the MIF-induced upregulation of the tyrosinase protein level. These results suggested that MIF is one of the important melanogens and a novel target to control the melanin content of UV-irradiated human skin. Moreover, Shirakami yeast extract might regulate the acceleration of melanogenesis by UV-induced MIF in the skin.